Diphtheria: a re-emerging public health challenge

Abstract

<p class="abstract">Diphtheria is a highly contagious, potentially life threatening bacterial infection caused by <em>Corynebacterium diphteriae. </em>Diphtheria is transmitted from person to person, usually through respiratory droplets and can lead to severe breathing problems, heart failure, blood disorders and death. Diphtheria was basically eliminated after the introduction of the vaccine in the 1940-1950s. However there is presently global concern that diphtheria is reemerging. We herein report nine cases of diphtheria presenting within a period of six months. All cases presented with sore throat, fever, membrane in the oropharynx and bull neck. Eight of the cases had never been immunized against diphtheria. All cases progressed and developed various complications with 8 of the cases dying. None of the cases had diphtheria antitoxin. This cases present the potential for this highly fatal but preventable disease reemerging and the need to be aware of epidemiological features, clinical signs and symptoms of diphtheria so that cases can be promptly diagnosed and treated, and further public health measures can be taken to contain this serious disease.</p>

Recurrent diphtheria outbreaks in Nigeria: A review of the underlying factors and remedies

“…Figure 1 depicts the pentavalent‐1 immunization coverage rate between 2017 and 2020 in Nigeria, dropping below the WHO's recommended 90% 5 . The high CFR seen in some of these outbreaks can be attributed to the scarcity of DAT, as Nigeria does not stock DAT 6,8 …”

“…9 India and other countries in Southeast Asia have contributed the bulk of the increasing incidence globally. 6 The incidence of diphtheria is underreported in Africa. The number of cases reported in Nigeria has been on the decline: 3995 in 2000 and 1870 in 2018.…”

“…In Nigeria, the official National Immunization Schedule prescribes an initial series of three DTP vaccine doses during infancy (administered at the 6th, 10th, and 14th weeks of life). Subsequently, booster doses are recommended at 16−24 months, followed by another at 5−6 years of age, and then at 10 and 16 years to cover for declining immunity over time 6 . The WHO advises that boosters should be customized to each country's disease epidemiology pattern 5 .…”

“…According to the World Health Organization (WHO), mass vaccination is the primary control measure for diphtheria 5 . The National Program on Immunization allows for a primary series of three doses of diphtheria−tetanus−pertussis (DTP) vaccine in infancy (at 6th, 10th, and 14th weeks), with booster doses after 10 years to cover for waning immunity 6 . Studies by Ibrahim et al and Besa et al have shown that declining herd immunity due to low vaccine coverage is the key determinant of previous outbreaks in the country, while the high mortality rate recorded is attributable to the nonavailability of diphtheria antitoxin (DAT) 7,8 …”

“…5 The National Program on Immunization allows for a primary series of three doses of diphtheria −tetanus−pertussis (DTP) vaccine in infancy (at 6th, 10th, and 14th weeks), with booster doses after 10 years to cover for waning immunity. 6 Studies by Ibrahim et al and Besa et al have shown that declining herd immunity due to low vaccine coverage is the key determinant of previous outbreaks in the country, while the high mortality rate recorded is attributable to the nonavailability of diphtheria antitoxin (DAT). 7,8 However, the underlying factors responsible for the low vaccine coverage in Nigeria and the barriers to the supply of DAT are yet to be examined.…”